In recent years, as a substrate for a display device for displaying an image or the like, a thin glass having excellent gas barrier properties, translucency or the like, that is, a glass film has been used. Currently, the thickness of a typical glass film is about 200 μm, but recently, an extremely thin glass film having a thickness of about 30 μm to 150 μm, which is thinner than 200 μm, has been developed.
Since such an extremely thin glass film has flexibility due to its thinness, it is possible to treat the glass film as a glass roll that is taken up in the form of roll. As the glass roll, for the purpose of preventing the glass film wound in the form of roll from being damaged by coming into contact with the glass film that is adjacent to an inner peripheral side and an outer peripheral side, there is a glass roll in which an interleaf (for example, a protective film) is interposed between the adjacent glass films.
Japanese Unexamined Patent Publication No. 2011-201765 discloses a method for manufacturing a glass roll in which an interleaf is interposed between the adjacent glass films.
The method for manufacturing the glass roll disclosed in Japanese Unexamined Patent Publication No. 2011-201765 is a method of manufacturing a glass roll in which a glass film is formed by a down-draw method and the formed glass film laminated onto an interleaf is taken up in the form of roll. In the manufacturing method, the glass film and the interleaf are taken up, while higher tension in a take-up direction is applied to the interleaf than to the glass film.
As a method of efficiently performing various treatments on such a glass film having flexibility, various techniques of performing various treatments such as coating on its surface, while winding off the glass film from the glass roll in which the long glass film is wound in the form of roll and transferring the glass film in a roll-to-roll manner, have been proposed.
As various treatments on the surface of the glass film, for example, there is a treatment that is performed in a vacuum chamber that is evacuated to the vicinity of the vacuum pressure, such as vacuum deposition or sputtering. Various effects due to the pressure change occur in the vessel that is evacuated to the vicinity of the vacuum pressure. For that reason, various techniques for performing the treatment (surface treatment) such as vacuum deposition or sputtering while transferring the glass film in consideration of the effects to be generated have been proposed.
Japanese Unexamined Patent Publication No. 2012-1405 discloses a transfer apparatus of the thin glass which transfers the thin glass under the vicinity of the vacuum pressure.
The transfer apparatus of the thin glass disclosed in Japanese Unexamined Patent Publication No. 2012-1405 is a transfer apparatus of a thin glass that includes a pressure control means capable of controlling the internal pressure of the vacuum chamber, and transfers the long thin glass in the vacuum chamber evacuated to the vicinity of the vacuum pressure. In the transfer apparatus, the pressure control means evacuates the internal pressure of the vacuum chamber to 10000 Pa over three minutes or longer, in a state in which the roll-shaped thin glass is disposed inside the vacuum chamber, and thereafter, evacuates the pressure to the vicinity of the vacuum pressure.
In the transfer apparatus of the thin glass, after evacuation under the conditions, the interleaf interposed between the thin glasses of the glass roll is detached from the thin glass during winding-off, and the thin glass is taken up in the form of roll, while interposing another interleaf between the thin glasses, when taking up the thin glass subjected to the surface treatment.
In addition, Japanese Unexamined Patent Publication No. 2008-189957 discloses a continuous deposition apparatus that winds off a substrate wound in the form of roll by having the interleaf laminated thereon while separating the substrate from the interleaf, and takes up the wound-off interleaf and the substrate subjected to the deposition process in the form of roll again.
The continuous deposition apparatus disclosed in Japanese Unexamined Patent Publication No. 2008-189957 has a wind-off roll that holds the substrate having the interleaf laminated thereon and taken up in the form of roll, and winds off the substrate and the interleaf; a wind-off section having a wind-off side support roller that rotatably supports the substrate, which is wound off from the wind-off roll, together with an interleaf so that the substrate comes into contact with the interleaf, and transfers it to the downstream side; a take-up side support roller that rotatably supports the substrate passed over the take-up side support roller and transfers it to the downstream side; a take-up section having a take-up roll that takes up the substrate via the take-up side support roller; and a deposition source that forms a film on the surface of the substrate that is continuously transferred in a state in which tension is applied to the take-up side support roller from the wind-off side support roller. In addition, the continuous deposition apparatus has an interleaf separating supply section. The interleaf separating supply section includes an interleaf separating and transferring means for separating the interleaf from the substrate and transferring it to the take-up side, when the substrate passes through the wind-off side support roller together with the interleaf; and an interleaf transferring and supplying means that supplies the interleaf separately transferred by the interleaf separating and transferring means when the substrate after the deposition is supported on the take-up side support roller while being transferred to the substrate so as to be brought into contact with the take-up side support roller and to be laminated on the substrate.
According to the continuous deposition apparatus, it is possible to form a film without causing defects in the substrate.
The continuous deposition apparatus of Japanese Unexamined Patent Publication No. 2008-189957 is not intended to mean the treatment, particularly, aimed at the glass film. However, a configuration of the apparatus, that is, a configuration which separately transfers the interleaf from the deposition target, and takes up the deposition target while laminating the interleaf onto the deposition target is considered to be a preferred configuration as a deposition apparatus of the glass roll described in Japanese Unexamined Patent Publication No. 2011-201765 in which the glass film and the interleaf are laminated.
In order to perform the surface treatment or the like on the thin glass (glass film) manufactured by the manufacturing method of Japanese Unexamined Patent Publication No. 2011-201765, the case of adopting a continuous deposition apparatus of Japanese Unexamined Patent Publication No. 2008-189957 is considered.
The continuous deposition apparatus of Japanese Unexamined Patent Publication No. 2008-189957 is designed based on the assumption that each of the substrate and the interleaf is a resin-based material. For that reason, when the thin glass as an inorganic material is adopted as the substrate in the continuous deposition apparatus of Japanese Unexamined Patent Publication No. 2008-189957 as in Japanese Unexamined Patent Publication No. 2012-1405, the following problem arises.
That is, the interleaf (protective film) as a resin-based material is transferred in a vacuum, moisture and organic substances contained therein are evaporated, and the interleaf shrinks. On the other hand, the glass film as the inorganic substance does not shrink. Therefore, as in the continuous deposition apparatus of Japanese Unexamined Patent Publication No. 2008-189957, when the wound-off interleaf is taken up in the form of roll again together with the glass film, the interleaf becomes shorter than the glass film by the shrinkage to apply excessive force to the glass film, or strong wrinkles are generated by excessive tension, which may lead to damage to the glass film.
Conversely, the interleaf as a resin-based material may also be sometimes stretched by the applied tension, depending on the material and thickness. In this case, the interleaf loosens when taking up the interleaf, the interleaf becomes wavy, and the glass film may be damaged by the unevenness of the wavy interleaf.
That is, in the case of the glass film as a treating target, when the interleaf made of resin laminated onto the glass film that are laminated are taken up, if these films are simply laminated and taken up, slight waviness or the like occurring when taking up the interleaf may cause damage to the glass film.